Tumors in living organisms are highly variable in size, location and their amount of infiltration into normal tissues, the variability of tumors in general make them very difficult to treat with a one-size fits all approach. Furthermore, the extent of tumors and/or void upon debulking are typically not known until presented in the operating room. Thus the options necessary to effectively treat a tumor or tumor bed need to be quite diverse.
Tumors are difficult to eradicate surgically as their infiltrative nature often precludes microscopically complete resection without undue morbidity or mortality. This local persistence of tumor cells may be controlled if sufficient radiation can be delivered safely prior to regrowth and replication of the residual tumor cells. Debulking surgery, followed by radiation therapy in high doses, provides the best chance for local control of a tumor. However, the ability to deliver high doses of radiation in the post operative setting is frequently limited by intolerance of surrounding healthy tissue. Radiation therapy is divided into external beam radiation therapy (EBRT) or teletherapy and internal radiation therapy or brachytherapy (BT). The therapeutic index is the relative amount of healthy tissue receiving high doses of radiation compared to the dose delivered to the tumor or tumor bed. Improving the therapeutic index may increase local control of tumors and/or decrease the morbidity of treatment. The inherently localized nature of BT is recognized as a technique to improve the therapeutic index in tumor treatment with radiation.
Brachytherapy involves placing a radiation source either into or immediately adjacent to a tumor. It provides an effective treatment of tumors of many body sites. Brachytherapy, as a component of multimodality cancer care, provides cost-effective treatment. Brachytherapy may be intracavitary, as in gynecologic malignancies; intraluminal, as in but not limited to esophageal or lung cancers; external surface, as in but not limited to cancers of the skin, or interstitial, as in but not limited to the treatment of various central nervous system tumors as well as extracranial tumors of the head and neck, lung, soft tissue, gynecologic sites, rectum, liver, prostate, and penis.
The currently available brachytherapy devices and techniques are lacking in the following areas: 1) the current carriers are unable to easily accommodate anatomically conformal and reproducible brachytherapy doses; 2) do not facilitate real-time dosimetric customization for sparing normal tissue, while delivering effective and safe doses of radiation to tumors; and 3) are not able to incorporate additional therapeutic agents, including chemotherapy, and viral, targeted, and DNA damage repair inhibitors.
The present invention addresses the deficiencies associated with current brachytherapy devices for treating highly variable tumors and comprises of novel brachytherapy radioisotope carrier systems and methodology for providing real-time customized brachytherapy treatment to patients with tumors difficult to control using conventional radiation therapy techniques.